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Updated: Jul 13, 2026
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Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli
Published on: August 18, 2023
Question 6: coevolution theory of the genetic code: a proven theory
1Department of Biochemistry and Applied Genomics Laboratory, Hong Kong University of Science & Technology, Clear Water Bay, Hong Kong, China. bcjtw@ust.hk
Summary
The coevolution theory explains the genetic code's structure, proposing early proteins used readily available amino acids. Genetic code mutants and comparative genomics provide rigorous proof for this theory.
Area of Science:
- Biochemistry
- Molecular Biology
- Evolutionary Biology
Background:
- The origin of the genetic code and its amino acid composition remains a fundamental question in molecular evolution.
- The coevolution theory posits that the genetic code expanded incrementally, incorporating amino acids as biosynthetic pathways evolved.
Purpose of the Study:
- To provide rigorous proof for the four fundamental tenets of the coevolution theory.
- To solve the riddle of the universal genetic code's structure.
Main Methods:
- Analysis of genetic code mutants.
- Comparative genomics of transfer RNAs (tRNAs) and aminoacyl-tRNA synthetases.
- Investigating the antiquity of pre-translational synthesis.
Main Results:
- Evidence from genetic code mutants supports the incremental expansion of the code.
- Comparative genomics reveals the ancient origins of key translational machinery.
- These findings rigorously validate the coevolution theory's core principles.
Conclusions:
- The coevolution theory offers a robust explanation for the structure of the universal genetic code.
- The study solves a long-standing riddle by demonstrating how the code evolved with available amino acids and biosynthetic pathways.
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